Petroleum lubricating jelly



No; 2,056,594 of Henry A. Ambrose.

tropic petroleum jelliesare mixtures of lubricat- Patented May 25, 1943 UNITED STATES PATENT OFFICE, ,1

' PETROLEUM LUBRICATING JELLY William A..Lutz, Oakinont, Pa., and John w. Pool, Akron, Ohio, assignorsto. Gulf Research & Development Company, Pittsburgh, Pa, a

corporation of Delaware No Drawing. Application nu ust zz, 1941, V Serial No. 407,982

- Claims.

This invention relates to improved petroleum lubricating .jellies; and it is particularly concerned with providing thixotropic petroleum jellies having improved viscosity-temperature characteristicsand improved lubricating properties, said jellies consistingessentially of a mixture of a petroleum lubricating oil with wax having a wax melting point above about 150 F. and having. incorporated therein an aluminum soap in such amount that the ratio of soap to wax cash registersand measuring instruments includlng airplane instruments, it is desirable that the lubricant be of such consistency that it will remain between the working surfaces and not be lost by dripping or leakage. At the same time it is desirable that the lubricant be of relatively low viscosity under operating conditions so as not to impede the operation of the mechanism. Liquld oil is not suitable because it will'leak, while greases are too viscous.

For this type of lubrication petrolatums have been used extensively in the past but are subject to the disadvantage that they have relatively low 'melting points and tum liquid at about .123 F. ln additlon, they showat low temperatures a high resistance to, shear. Plastic petroleum jellies having melting points higher than petrolatum and having .t'hixotroplc properties, that is, of

= jelly-like consistency when quiescent and liquid when, agitated, have more recently been recommended for such uses in United States Patent These thixoing oils, advantageously lubricating oils having high viscosity-indices with waxes having melting points above about 150 F. and they have proved tobe advantageous substitutes for petrolatum not entirely satisfactory. V

It is an object of the present invention to improve the temperature-viscosity characteristics and running torque of thixotropic wax-oil mixtures and to provide thixotropic petroleum jellies having melting points above that of petrolatum which have high penetration and low running torque properties at low temperatures.

We have discovered that when aluminum soap such as aluminum stearate or aluminum oleate is incorporated in thixotropic mixtures of wax and oil in such amount that the ratio of soap to wax is substantially less than'lzl, the soap is completely taken up bythe wax and does not act as a thickening agent for the oil. The resulting composition is a product which while retaining its thixotropic properties has a higher penetration and a lower running torqueat lowiemperatures than the original wax-oil mixture. This combination of properties makes these compositions particularly valuable for certain types 'of lubrication, such for example as in .the lubrieating of aircraft instruments and control bearings. Because of their thixotropic properties these compositions areabetter retainedin the bearings at elevated temperatures, and because of their relative softness at low temperatures as indicated by their high penetration and low running torque at low temperatures they function satisfactorily as lubricants over the broadtem- 'perature range to which suchbearlngs are subjected.

In preparing the improved thixotropic jellies of my invention,- wax of high wax melting point, advantageously wax substantially free from oil and having an A. S. .T M. wax melting point above about 150 F. is used. Ceresin wax such as is obtained from ozokerite having an A. S. T.

M. wax melting point of about 160 F. has proved particularly satisfactory, although other waxes 'may be used such as petroleum ceresin or refined rod wax,v montan wax, shellac wax or mixtures of these waxes with oil-free petroleum waxes having melting points above about 150 F. The amount of wax used may be'varied widely depending on the particular wax used and the properties desired in the lubricant. In general,

I the amount of wax used should be sufficient to provide an oil-wax mixture having a cloud point above about F. In order to obtain this cloud point, at least about 4.0 per cent by weight of wax havinga melting point above about usually required.

The oil used in forming the thixotropic jellies jelly maybe varied to regulate the temperature of soap ;torwax inuthe finishedjelly-is less thanv stantially any oil properly designated as a lubricating oil may be used depending upon its intended application. Thus oils having viscositles as low as 80 S. U. V. and as high as 3500 S. U. V.

at 100 F. may be used under appropriate cir-- For this reason'we'find aluminum chloride refined lubricatingoils and other highlyparafinic oils to be most-suitable. The percentage of oil in the consistency characteristics of the lubricant. The aluminum soap may be aluminum monomay also be used and we have obtained very good dior tri-stearate, oleate, palmitate or other' compound of aluminum with ila 'highm'olecular I weight fatty acid. Mixtures of aluminum soaps" u 2,320,0oa may vary widely in properties. In general, subcating-oil having a viscosity of 58 S. U. V. at 100 f1, and ceresin wax:

The softening effect of the aluminun stearate is point ,The penetration and drop point values.

were determinedby the standard methods of the American Society for Testing Materials.

'* The efiect'ot aluminum stearate additions on 1 mi x"li; lum a resu ts wlth xtures for 8 amp 8 of a mum trated in the results shown in Table 2. These di-stearate and aluminum tri-stearatei The invention in amounts such that the weight ratio 'l-:::1' andwe'have obtainedsatisfactory resultsrusing" ratios'of soap t0 'waxas ,low as 12.15. Inmost .casesswe have found itadvantageous to use ratios The jlliesbecomezless thixotropic with a higher 'ratios'of. soap to :wax while "theirzmelting points increase and their mechanical stability is; :im-

':proved.'..- i Incompounding these: thixotropic, :lubricants gether.

the wax and oil are'customarily'first. melted to.-

.The aluminum soap, is: then added to r the twax' -oil .mixture at a temperature below the gel point of the mixture, 1 usually below about 1170 F;:'and the wholemixtureis then heated to a-temperatureof -200- F. or-higherzto melt 1 it.

:The meltedmixturesmay then be: poured and cooleds-under regulated conditionsvUnlike -g'rease's,"these thixotropic. mixtures return-to -jellylike consistency after being heated above the melting point-of-ithe wax and .cooled. The

:--'rate :ofwsouling. is: advantageously. carefully regulated..zThe melting point and consistency. of the jell'ysobtained .vary" somewhat. depending on the ertiesasi-nearlyias possible in successive batches .or:'the-.-same compositionit is :desirablethat the "batches 'be .cooled' atabout :the same rate.- Slow cooling produces somewhat softer products than more rapid cooling. The harder productsobe tainedwith more :rapidrcooling are 'less stable than'islow. cooled products:

The thixotropic petroleum" lubricating jellies containing=aluminum soaps thus produced are "characterized by being zsofter-tlian corresponding thixotropicr'mixtures of waxrand oil .without soap and they have higher penetration values and lower running-torques, particularly. at low temperatures. These improved 1 viscosity-temperaturecharacteristics'permit the use of these "jelly lubricants in cases where very wide temperature difiereu'ces areencountered with improvedlubrication throughout the range. e

j The following examples-1 illustrate: the admg aluminum" soaps "in? thixotropic vantageous properties obtained-by incorporatpetroleum I In these tests" the running torque of thixotropic jellies is illusvalues were determined on a B. E. C. machine,

"named for the Bearing Engineers Committee,

as described in Product Engineering, volume 7,

i age1f255j 193axthe only deviation bein'g the us'e of ,dry ice and acetone to maintain thelow temperature.

I the bearing was packed withf4.5 gramsof .jelly and cooled'tofthejlowest possible temperature. .Atj intervals as the machine warmed up the motor was started "and'tor'que [data was recorded.f The machine was-1 then [Tstopp'e'dand allowed toincrasefurther in temrate of'-coolingi:and in ordehto reproduce prop-L I I v p eratur'e and tainingno soap. 'A comparison of I, determined is given in Table 2. f V

n I again started, and'another set: of

"torque datafwas recorded. j V V n The runiiingfltorqu'e' values at various temperatures were determined on an aluminum'chloride v refined lubricating oil of 58 ISL U. V. at 100 F.,

on a thixotropic petroleum jelly'fc'ontalnins aluminum stearate and on an oil-wax jelly conthe values v Aid Etc; '01; 07 '0' 5 "me 19 i 1,, f' white ceresin ceres n It is apparent these results thataluminum stearate hasa very beneficial effect on the running torque of wax-oil :mixtures; particularly at a low temperatures. It will be seen from a .com-

parison ofthe results obtained on oil alone, on the same oil plus 510% ceresin wax andion a jelly containing both ceresin'wwax' and aluminum --stearate 'in'admixture with thesame type oil,

that at ordinary temperature the runnin 'torque --of' the jelly is about't'he same as -that offthe oil r nd lowerthan that of the oil-'-wax mixture,

' and'at lower temperatures, that'is below:zer0 Fahrenheit; is substantially lower than that of 'the'wax-oil mixture or of oil alone;

In the followingTablet there are shownthe physical properties of thixotropic Y petroleum =jellies containing varying proportionsof aluminum vsoap'and 0 1s of different viscosities' and mixtures of aluminum 'diand tri=stearate as compared with thixotropic petroleum jellies conproximately 1:15, whereby the penetration of the jelly at low temperatures is substantially intaining noaluminum soap.

Sample V 1 Aluminum di-stearute.. Aluminum tri-stearate... Oeresin w Pro erties:

elting oint F. UbbeL. Penetgajt on, unworked,-

100 F Penetration, worked, 77 F From these results the beneficial effect of aluminum soaps in increasing the melting point, and the -penetration, particularly at low temperatures, of thixotropic oil-wax jellies is apparent.

While our invention has been described herein with reference to certain specific embodiments thereof by way of example, it is to be understood that my invention is not limited thereto except as hereinafter defined in the appended claims. The striking properties of the product obviously render it eminently suitable for use in substantially all of the relationships wherein petroleum jellies are customarily employed. It will be understood that when the jelly is to be employed as a base for salves or unguent medicaments, it is advantageously prepared under conditions assuring high purity and sterility.

What we claim is: 3

l. A thixotropic petroleum lubricating jelly,

having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially ot a mixture of a petroleum lubricating oil with a wax having a wax melting point above about 150 F., and having incorporated therein an amount of aluminum soa such that the ratio of soap to wax by weight is less than 1:1 but at least approximately 1:15, whereby the jelly is rendered substantially softer at low temperatures.

2. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially of a mixture of a petroleum lubricating oil with a wax having a wax melting point above about 150" F. in amount sufficient .to provide a wax-oil mixture having a cloud point above about 145 F., and having incorporated therein an amount of aluminum soap such that the ratio of soap to wax by weight is less than 1:1 but at least approximately 1:15, whereby the penetration of the jelly at low temperatures is substantially increased, and the running torque of the jelly at low temperatures is substantially decreased.

3. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially of a mixture of a. petroleum lubricating oil having aviscosity index above about 90, with a wax having a wax melting point above about 150 F. in an. amount sufiicient to provide a wax-oil mixture having a cloud point above about 145 F., and having incorporated therein an amount of aluminum soap such that the ratioof soap to wax by weight. is less than 1:1 but at least apcreased, and the running torque of the jelly at low temperatures is substantially decreased.

4. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially of a mixture of a petroleum lubricating oil having a viscosity,index above about with ceresin wax, and having incorporated therein an amount of aluminum soap such that the ratio of soap to wax by weight is less than 1:1 but at least approximately 1: 15, whereby the penetration of the jelly at low temperatures is substantially increased, and the running torque of the jelly at low temperatures is substantially decreased.

5. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at 5 low temperatures, consisting essentially of a mixture of a petroleum lubricating oil with a wax having a melting point; above about 150 F. in an amount suflicient to provide a wax-oil mixture having a cloud point alifie about F., and having incorporated .therein a substantial amount of aluminum stearate such that the ratio of aluminum stearate to wax by weight is less than 1:1, whereby the penetration of the jelly at low temperatures is substantially increased, and the running torque of the jelly at low temperatures is substantially decreased.

6. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially of a mixture of a petroleum lubricating oil with a wax having a wax melting point above about F. in an amount sufficient to provide a wax-oil mixture having a cloud point above about 145 F., and having incorporated therein an amount of aluminum stearate such that the ratio of aluminum stearate to wax by weight is between 1:1 and 1:15.

7. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature characteristics and improved lubricating properties at low temperatures, consisting essentially of a mixture of a petroleum lubricating oil having a viscosity index above about 90, with ceresin wax in an amount sufiicient to provide a wax-oil mixture having a cloud point above about 145 F., and having incorporated therein a substantial amount of aluminum stearate such that the.

ratio of aluminum stearate to wax by weight is less than 1:1, whereby the penetration of the jelly at low temperatures is substantially increased, and the running torque of the jelly at low temperatures is substantially decreased.

8. A thixotropic petroleum lubricating jelly,

low temperatures, consisting essentially of a mixture of a'petroleum lubricating oil'having a vis j cosity index above about 90, with 'ceresin wax in an amount suflicient to provide a wax-oil mixture havinga cloud point above about 145 F., .and having incorporated therein an amount of aluminum stearate such that the ratio of aluminum stearate tovwax by weight is between 1:1 and 1:15.

I 9. A thixotropic petroleum lubricating jelly, having improved viscosity-temperature charac I teristics and improved lubricating'properties at low temperatures, consisting essentially of a mix in substantial amount which amount is less I V 1 2,820,002 having improved viscosity-temperature charac 'teristica andimproved lubricating properties at than the quantity which bears a ratio of l:1 by weight to the wax present, whereby the jelly is rendered substantially soiter at low temperatures. 10,4 thixotropic petroleum lubricating jelly, :having improved viscosity-temperature characteristics and improved'lubricating properties'at low temperatures, consisting essentially oi' a mixture of a petroleum lubricating oil with a wax having a wax melting point above about'150 l". in amount sufllcient to provide a wax-oil'mixture having a cloud point above about 145 F. and having incorporated therein analuminum soap in substantial amount which amount is less than the quantity which bears a ratio of 1:1 by weight of the wax present, whereby the Jelly is rendered substantially softer at low temperatures.

WILLIAM A. LUTZ. JOHN Wr POOL. 

